Table IV.
Estimates of Genetic and Environmental Variances and Covariances (95% CI) From the Full Model and Reduced Model
| Full Model |
Reduced Model |
|||||
|---|---|---|---|---|---|---|
| Variance Within Age | h2 | c2 | e2 | h2 | c2 | e2 |
| SP age 2 | .55 (.32 to.74) | .14 (.00 to .33) | .31 (.24 to .41) | .69 (.60 to .76) | – | .31 (.24 to .40) |
| SP age 3 | .57 (.36 to .76) | .13 (.00 to .32) | .29 (.23 to .39) | .71 (.62 to .78) | – | .29 (.22 to .38) |
| Covariance across age | rg | rc | re | rg | rc | re |
| SP age 2 —SP age 3 | .62 (.40 to .76) | 1.00 (−1.00 to 1.00) | .25 (.08 to .41) | .69 (.58 to .79) | – | .23 (.06 to .38) |
Note. SP = sleep problems; h2 = genetic variance; c2 = shared environmental variance; e2 = nonshared environmental variance; CI = confidence interval. rg, rc, and re denote the genetic, shared-environmental, and nonshared environmental correlations, respectively.